Electronic tuning system and methods of using same

Abstract

A system and methods for assisting a technician in tuning a musical instrument exhibiting inharmonicity, such as a piano. A display informs the technician of one or more beat rates associated with respective intervals of a note being tuned and other notes. A second display informs the technician of the phase difference between the note being adjusted and a reference signal. The note being tuned is detected automatically, thereby allowing the technician to work without constantly touching the system. The wavelengths emanating from the notes are determined accurately, and the corresponding frequencies are tested for their quality before being used in calculations used for providing the information for the displays. A tuning frequency is calculated for each note after measurement of a first note, and the calculation is updated as more measurements are taken. If desired, the technician may visit each note only once in the tuning of the musical instrument.

What is claimed is:  
     
       1. A method for use in the tuning of a musical instrument having multiple adjustable frequency tone generators, each said tone generator capable of producing one or more different order partials, with the first partial for each tone generator corresponding to the lowest frequency of said each tone generator, the method comprising: 
       measuring at least two partials for each of at least one tone generator of the multiple tone generators;  
       calculating at least one inharmonicity value, each inharmonicity value representing a relationship between two of said measured at least two partials of a respective at least one tone generator;  
       estimating at least one inharmonicity value for at least one other tone generator of the multiple tone generators based upon the calculated at least one inharmonicity value; and  
       calculating a target frequency for at least one partial for at least one of the multiple tone generators based upon said calculated at least one inharmonicity value and said estimated at least one inharmonicity value.  
     
     
       2. The method of  claim 1 , wherein said calculating a target frequency for at least one partial comprises calculating a target frequency for at least one partial for each of a plurality of the multiple tone generators. 
     
     
       3. The method of  claim 1 , wherein said calculating a target frequency, for at least one partial comprises calculating a target frequency for substantially all measured partials of at least one of the multiple tone generators. 
     
     
       4. The method of  claim 1 , wherein calculating a target frequency for at least one partial comprises calculating a target frequency for substantially all measured partials of a plurality of the multiple tone generators. 
     
     
       5. The method of  claim 1 , further comprising 
       displaying a indicator representative of at least one calculated target frequency.  
     
     
       6. The method of  claim 1 , further comprising 
       calculating a difference between said calculated target frequency and a substantially real-time frequency of a partial; and  
       displaying an indicator representative of said calculated difference.  
     
     
       7. The method of  claim 6 , further comprising 
       generating a reference signal based upon a calculated target frequency of a partial,  
       wherein said indicator is representative of a phase difference between said generated reference signal and said substantially real-time phase of said partial.  
     
     
       8. The method of  claim 7 , wherein said indicator is representative of a cumulative phase difference between said generated target frequency and said substantially real-time phase of said partial. 
     
     
       9. The method of  claim 1 , further comprising 
       adjusting at least one the multiple tone generators based on one of its said respective calculated target frequencies.  
     
     
       10. The method of  claim 6 , adjusting at least one the multiple tone generators based on said indicator. 
     
     
       11. The method of  claim 1 , wherein said plurality of values includes a value for each unique pair of partials among at least three partials. 
     
     
       12. The method of  claim 11 , wherein said at least three partials comprises substantially all measured partials of a given tone generator. 
     
     
       13. The method of  claim 1 , further comprising: 
       measuring at least two partials of a second tone generator;  
       calculating at least one inharmonicity value, each inharmonicity value representing a relationship between two of said measured at least two partials of said second tone generator; and  
       calculating a target frequency for at least one partial of said second tone generator based upon at least one of said at least one measured inharmonicity value and at least one of said at least one estimated inharmonicity value.  
     
     
       14. The method of  claim 13 , further comprising: 
       adjusting said second tone generator based upon said at least one calculated target frequency for said second tone generator.  
     
     
       15. The method of  claim 14 , further comprising: 
       (a) measuring at least two partials of another of said plurality of the multiple tone generators;  
       (b) calculating at least one inharmonicity value for said another tone generator, each inharmonicity value representing a relationship between two of said measured at least two partials of said another tone generator;  
       (c) calculating a target frequency for at least one partial of said another tone generator based upon at least one of said measured at least one inharmonicity value and at least one at least one of said at least one estimated inharmonicity value;  
       (d) adjusting said another tone generator based upon at least one said calculated target frequency for another tone generator; and  
       (e) repeating (a)-(d) for a plurality of remaining tone generators of the multiple tone generators.  
     
     
       16. A method for use in the tuning of a musical instrument having multiple adjustable frequency tone generators, each said tone generator capable of producing one or more different order partials, with the first partial for each tone generator corresponding to the lowest frequency of said each tone generator, the method comprising: 
       measuring at least three partials of a first tone generator;  
       calculating at least three inharmonicity values, each inharmonicity value representing a relationship between two of said measured at least three partials of said first tone generator;  
       estimating at least one inharmonicity value for each of a plurality of the multiple tone generators, each estimated inharmonicity value representing a relationship between two estimated partials of the respective tone generator; and  
       calculating a target frequency for at least one partial of said first tone generator based upon at least one of said at least one calculated inharmonicity value and at least one of said at least one estimated inharmonicity value.  
     
     
       17. The method of  claim 16  further comprising: 
       adjusting said first tone generator based upon said at least one calculated target frequency for said first tone generator.  
     
     
       18. The method of  claim 17 , further comprising: 
       measuring at least three partials of a second tone generator;  
       calculating at least three inharmonicity values, each inharmonicity value representing a relationship between two of said measured at least three partials of said second tone generator;  
       estimating at least one inharmonicity value for each of a plurality of unmeasured tone generators, each estimated inharmonicity value representing a relationship between two estimated partials of the respective tone generator; and  
       calculating a target frequency for at least one partial of said second tone generator based upon at least one of said at least one measured inharmonicity value and at least one of said at least one estimated inharmonicity value.  
     
     
       19. The method of  claim 18 , further comprising: 
       adjusting said second tone generator based upon said at least one calculated target frequency for said second tone generator.  
     
     
       20. The method of  claim 19 , further comprising: 
       (a) measuring at least two partials of another of said plurality of the multiple tone generators;  
       (b) calculating at least three inharmonicity values for said another tone generator, each inharmonicity value representing a relationship between two of said measured at least two partials of said another tone generator;  
       (c) estimating at least one inharmonicity value for each of a plurality of unmeasured tone generators, each estimated inharmonicity value representing a relationship between two estimated partials of the respective tone generator;  
       (d) calculating a target frequency for at least one partial of said another tone generator based upon at least one of said measured at least one inharmonicity value and at least one at least one of said at least one estimated inharmonicity value;  
       (e) adjusting said another tone generator based upon at least one said calculated target frequency for another tone generator; and  
       (f) repeating (a)-(e) for a plurality of remaining tone generators of the multiple tone generators.  
     
     
       21. The method of  claim 16 , wherein said at least inharmonicity values includes a value for each unique pair of partials among at least three partials. 
     
     
       22. A system for use in the tuning of musical instrument having multiple adjustable frequency tone generators, each said tone generator capable of producing a plurality of different order partials, with the first partial for each note corresponding to the lowest frequency of the note, the system comprising: 
       a wave sampler capable of converting sound into an electrical signal;  
       a signal processor receiving said signal, said signal processor adapted to measure a plurality of partials based on said signal and generate a plurality of inharmonicity values, each inharmonicity value representing a relationship between two of said measured plurality of partials of a respective tone generator; and  
       a calculator capable of estimating at least one inharmonicity value for at least one tone generator based upon at least one of said signals generated by said signal processor and calculating a target frequency for at least one partial of at least one tone generator of the multiple tone generators based upon said inharmonicity values.  
     
     
       23. The system of  claim 22 , wherein said plurality of values comprises a value for each unique pair of partials among said plurality of partials of the respective tone generator. 
     
     
       24. The system of  claim 22 , wherein said plurality of partials comprises substantially all measured partials of the respective tone generator. 
     
     
       25. The system of  claim 22 , wherein said calculator is adapted to calculate a target frequency for at least one partial of substantially all of the multiple tone generators. 
     
     
       26. The system of  claim 22 , wherein said calculator is adapted to calculate a target frequency for each of substantially all measured partials of substantially all of the multiple tone generators. 
     
     
       27. The system of  claim 22 , further comprising 
       a display capable of displaying an indicator representative of at least one of said calculated target frequencies.  
     
     
       28. The system of  claim 22 , further comprising 
       a display capable of displaying an indicator representative of a difference between at least one of said calculated target frequencies and a substantially real-time frequency of a partial of the respective tone generator.  
     
     
       29. The system of  claim 22 , further comprising a reference signal generator capable of generating a reference signal representative of the calculated target frequency for a partial of a respective tone generator, and wherein said indicator is representative of a phase difference between said generated reference signal and said substantially real-time phase of said partial of said respective tone generator. 
     
     
       30. A method for use in tuning of a musical instrument having multiple adjustable frequency tone generators, each said tone generator capable of producing one or more different order partials, with the first partial for each tone generator corresponding to the lowest frequency of said each tone generator, the method comprising: 
       (a) measuring at least two partials of a first tone generator;  
       (b) calculating a target frequency for each of at least one partial of each of a plurality of the multiple tone generators;  
       (c) adjusting said first tone generator based upon said calculated target frequency;  
       (d) measuring at least one partial of another tone generator;  
       (e) calculating a target frequency for each of at least one partial of each of a plurality of the multiple tone generators;  
       (f) adjusting said another tone generator based upon said calculated target frequency; and  
       (g) repeating (d)-(f) for other tone generators of said plurality of tone generators until substantially all of said plurality of tine generators have been adjusted, wherein each of said plurality of the multiple tone generators is-adjusted to a final state before another tone generator is measured, and no other tone generators are measured before said first tone generator.  
     
     
       31. The method of  claim 30 , wherein measurement and adjustment of each said tone generator occurs substantially simultaneously. 
     
     
       32. A method for use in tuning of a musical instrument having multiple adjustable frequency tone generators, each said tone generator capable of producing one or more different order partials, with the first partial for each tone generator corresponding to the lowest frequency of said each tone generator, the method comprising the steps of: 
       (a) providing a tuning calculator capable of calculating tuning information for the musical instrument based upon measured partials;  
       (b) measuring at least two partials of a selected tone generator of a plurality of tone generators of the musical instrument and providing the measurements to the tuning calculator for calculation of the tuning information;  
       (c) adjusting said selected tone generator based upon tuning information provided by said tuning calculator; and  
       (d) repeating steps (b) and (c) for each of said plurality of tone generators; wherein each tone generator of said plurality of tone generators is adjusted before another tone generator is measured.  
     
     
       33. The method of  claim 32 , wherein said adjusting is performed by a technician. 
     
     
       34. The method of  claim 33 , wherein the tuning information calculated by the tuning calculator is provided to the technician by a visual display. 
     
     
       35. The method of  claim 32 , wherein each of said plurality of tone generators is adjusted to a final state before another tone generator of said plurality of tone generators is measured. 
     
     
       36. The method of  claim 32 , wherein said musical instrument comprises a piano. 
     
     
       37. The method of  claim 32 , wherein said calculated tuning information comprises at least one target tuning frequency. 
     
     
       38. The method of  claim 37 , wherein said at least one target tuning frequency comprises a target tuning frequency for said selected tone generator. 
     
     
       39. The method of  claim 38 , wherein a target tuning frequency for a respective selected tone generator is calculated by said tuning calculator after measurement of said respective selected tone generator. 
     
     
       40. The method of  claim 37 , wherein said tuning information further comprises a plurality of inharmonicity values, each inharmonicity value representing a relationship between two partials of a respective tone generator of the plurality of tone generators. 
     
     
       41. The method of  claim 40 , wherein at least one of said inharmonicity values is calculated based upon measured partials. 
     
     
       42. The method of  claim 41 , wherein at least one of said inharmonicity values is estimated. 
     
     
       43. The method of  claim 32 , wherein the tuning information becomes progressively more accurate as the partials of more tone generators of said plurality of tone generators are measured. 
     
     
       44. The method of  claim 38 , further comprising, prior to step (c), calculating a phase difference between a measured partial of said selected tone generator and said calculated target tuning frequency of said selected tone generator.